• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
• | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
• | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
Circuit | Short to Ground | Open/High Resistance | Short to Voltage |
---|---|---|---|
Ignition 1 Voltage | P0973, P0976, P2764 | P0973, P0976, P2764 | -- |
1-2 SS Valve Control | P0973 | P0973 | P0974 |
2-3 SS Valve Control | P0976 | P0976 | P0977 |
TCC PWM Valve Control | P2764 | P2764 | P2763 |
Circuit | Normal | Short to Ground | Open/High Resistance | Short to Voltage |
---|---|---|---|---|
Operating Conditions: Engine running, normal operating temperature Parameter Normal Range: OK | ||||
1-2 Sol. CKT Status | OK | Open/Short to GND | Open/Short to GND | Short to Volts |
2-3 Sol. CKT Status | OK | Open/Short to GND | Open/Short to GND | Short to Volts |
TCC Duty Cycle CKT Status | OK | Open/Short to GND | Open/Short to GND | Short to Volts |
The 1-2 shift solenoid (SS) and the 2-3 SS valves control transmission fluid pressure acting on the shift valves to position the valves for the appropriate gear. The 1-2 SS and the 2-3 SS valves are normally-open exhaust valves located on the control valve body. A fused circuit supplies ignition voltage to the 1-2 SS valve and the 2-3 SS valve. The transmission control module (TCM) commands the solenoid ON or OFF by switching the ground path. When the 1-2 SS valve or the 2-3 SS valve is commanded ON, the TCM senses low voltage. When the 1-2 SS valve or the 2-3 SS valve is commanded OFF, the TCM senses high voltage.
The engine speed is greater than 500 RPM for 2 seconds.
The TCM detects an open or short to ground on the 2-3 SS valve control circuit for 4.4 seconds.
The TCM detects a short to voltage on the 2-3 SS valve control circuit for 4.4 seconds.
• | DTC P0976 is a Type A DTC. |
• | The TCM inhibits 1st and 4th gear. |
• | The TCM forces the TCC solenoid OFF. |
• | The TCM commands maximum line pressure. |
• | The TCM freezes transmission adaptive functions. |
• | The Hybrid control module (HCM) inhibits Hybrid operation. |
• | DTC P0977 is a Type A DTC. |
• | The TCM inhibits 4th gear. |
• | The TCM commands maximum line pressure. |
• | The TCM freezes transmission adaptive functions. |
• | The Hybrid control module (HCM) inhibits Hybrid operation. |
DTCs P0976 and P0977 are Type A DTCs.
Automatic Transmission Controls Schematics
Electronic Component Description for Shift Solenoid Valves 1-2 and 2-3 information
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Control Module References for scan tool information
J 44152 Jumper Harness (20 pins)
Important: Additional DTCs may set when disconnecting the automatic transmission inline 20-way connector.
⇒ | If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance. If the circuit tests normal and the ignition circuit fuse is open, test all components connected to the ignition circuit and replace as necessary. |
⇒ | If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the TCM. |
⇒ | If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the TCM. |
⇒ | If not within the specified range, test the circuits for a short to ground or an open/high resistance. If a circuit is shorted or open replace the internal transmission harness, if the circuits test normal, replace the 2-3 shift solenoid. |
⇒ | If not the specified value, test the circuits for a short to ground or an open/high resistance. If a circuit is shorted replace the internal transmission harness, if the circuits test normal, replace the 2-3 shift solenoid. |
Perform the Diagnostic Repair Verification after completing the repair.
• | Control Module References for TCM replacement, setup, and reprogramming |
• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
• | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
• | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
Circuit | Short to Ground | Open/High Resistance | Short to Voltage |
---|---|---|---|
Ignition 1 Voltage | P0973, P0976, P2764 | P0973, P0976, P2764 | -- |
1-2 SS Valve Control | P0973 | P0973 | P0974 |
2-3 SS Valve Control | P0976 | P0976 | P0977 |
TCC PWM Valve Control | P2764 | P2764 | P2763 |
Circuit | Normal | Short to Ground | Open/High Resistance | Short to Voltage |
---|---|---|---|---|
Operating Conditions: Engine running, normal operating temperature Parameter Normal Range: OK | ||||
1-2 Sol. CKT Status | OK | Open/Short to GND | Open/Short to GND | Short to Volts |
2-3 Sol. CKT Status | OK | Open/Short to GND | Open/Short to GND | Short to Volts |
TCC Duty Cycle CKT Status | OK | Open/Short to GND | Open/Short to GND | Short to Volts |
The 1-2 shift solenoid (SS) valve and the 2-3 SS valves control transmission fluid pressure acting on the shift valves to position the valves for the appropriate gear. The 1-2 SS and the 2-3 SS valves are normally-open exhaust valves located on the control valve body. A fused circuit supplies ignition voltage to the 1-2 SS valve and the 2-3 SS valve. The transmission control module (TCM) commands the solenoid ON or OFF by switching the ground path. When the 1-2 SS valve or the 2-3 SS valve is commanded ON, the TCM senses low voltage. When the 1-2 SS valve or the 2-3 SS valve is commanded OFF, the TCM senses high voltage.
The engine speed is greater than 500 RPM for 2 seconds.
The TCM detects an open or short to ground on the 2-3 SS valve control circuit for 4.4 seconds.
The TCM detects a short to voltage on the 2-3 SS valve control circuit for 4.4 seconds.
• | DTC P0976 is a Type A DTC. |
• | The TCM inhibits 1st and 4th gear. |
• | The TCM commands maximum line pressure. |
• | The TCM freezes transmission adaptive functions. |
• | DTC P0977 is a Type A DTC. |
• | The TCM inhibits 4th gear. |
• | The TCM commands maximum line pressure. |
• | The TCM freezes transmission adaptive functions. |
DTCs P0976 and P0977 are Type A DTCs.
Automatic Transmission Controls Schematics
Electronic Component Description for Shift Solenoid Valves 1-2 and 2-3 information
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Control Module References for scan tool information
J 44152 Jumper Harness (20 pins)
Important: Additional DTCs may set when disconnecting the automatic transmission inline 20-way connector.
⇒ | If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance. If the circuit tests normal and the ignition circuit fuse is open, test all components connected to the ignition circuit and replace as necessary. |
⇒ | If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the TCM. |
⇒ | If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the TCM. |
⇒ | If not within the specified range, test the circuits for a short to ground or an open/high resistance. If a circuit is shorted or open replace the internal transmission harness, if the circuits test normal, replace the 2-3 shift solenoid. |
⇒ | If not the specified value, test the circuits for a short to ground or an open/high resistance. If a circuit is shorted replace the internal transmission harness, if the circuits test normal, replace the 2-3 shift solenoid. |
Perform the Diagnostic Repair Verification after completing the repair.
• | Control Module References for TCM replacement, setup, and reprogramming |